Preparation of single-helix carbon microcoils by catalytic CVD process

Three-dimensional (3D) single-helix spring-like carbon microcoils (SH-CMCs) were obtained by the catalytic pyrolysis of acetylene at 800-820 degrees C over the Fe-Ni alloy catalysts; their growth morphologies and microstructure were examined. The diameter of carbon fiber, from which the carbon nanocoils was formed, was about 0.5 mu m, the coil diameter was about 1-2 mu m, and the coil pitch was about the same with the coil diameter. The SH-CMCs were generally grown by a double-directional growth mode. (c) 2007 Elsevier B.V. All rights reserved.